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Related papers: Probing the Przybylski star for Deuterium

200 papers

Debris disks are tenuous, dust-dominated disks commonly observed around stars over a wide range of ages. Those around main sequence stars are analogous to the Solar System's Kuiper Belt and Zodiacal light. The dust in debris disks is…

Earth and Planetary Astrophysics · Physics 2018-10-17 A. Meredith Hughes , Gaspard Duchene , Brenda Matthews

The presence of the lithium-6 isotope in some metal-poor stars is a matter of surprise because of the high values observed. Non-standard models of Big Bang nucleosynthesis and pre-Galactic cosmic ray fusion and spallation have been proposed…

Solar and Stellar Astrophysics · Physics 2009-09-29 A. E. Garcia Perez , W. Aoki , S. Inoue , S. G. Ryan , T. K. Suzuki , M. Chiba

We present high spectral resolution optical observations of comet 21P/Giacobini-Zinner from six nights in 2018. The observations were obtained with the Tull coude spectrograph on the 2.7m Harlan J. Smith Telescope of McDonald Observatory.…

Earth and Planetary Astrophysics · Physics 2020-09-04 Anita L. Cochran , Tyler Nelson , Adam J. McKay

We present FUSE observations of the line of sight to WD0439+466 (LS V +46 21), the central star of the old planetary nebula Sh2-216. The FUSE data shows absorption by many interstellar and stellar lines, in particular D I, H2 (J = 0 - 9),…

Astrophysics · Physics 2009-11-13 Cristina M Oliveira , Pierre Chayer , H. Warren Moos , Jeffrey W. Kruk , Thomas Rauch

The present understanding of type Ib/c supernovae and their connection to interacting binaries is reviewed. The problems of the classification and the lack of well-observed events exclude direct inference of progenitor characteristics. The…

Astrophysics · Physics 2016-08-30 Bruno Leibundgut

The use of a method of spectra disentangling for telluric lines is explained in detail, with a particular emphasis on high-precision radial-velocity measurements for the search for extrasolar planets. New improvements to the method are…

Astrophysics · Physics 2009-11-11 Petr Hadrava

There are $\sim3\sigma$ or more evidence of eV-scale sterile neutrinos from several different measurements. Many dedicated experiments are (being) created and (will) take data to confirm or refute the eV-scale sterile neutrinos. In this…

High Energy Physics - Experiment · Physics 2020-01-27 Seon-Hee Seo

We study the diffusive transport of neutrinos in a newly born neutron star to explore its sensitivity to dense matter properties. Energy and lepton number which are trapped during the catastrophic implosion diffuse out on the time scale of…

Astrophysics · Physics 2007-05-23 S. Reddy , J. Pons , M. Prakash , J. M. Lattimer

We report on a survey of \nh2d towards protostellar cores in low-mass star formation and quiescent regions in the Galaxy. Twenty-three out of thirty-two observed sources have significant ($\gsim 5\sigma$) \nh2d emission. Ion-molecule…

Astrophysics · Physics 2009-11-06 Ronak Y. Shah , H. Alwyn Wootten

Primordial evaluations of the deuterium abundance should provide one of the best tests of Big Bang nucleosynthesis models. Space as well as ground based observations seem however to result in different values. This asks for more…

Astrophysics · Physics 2016-11-03 A. Vidal-Madjar

A static, spherically symmetric spacetime with negative pressures is conjectured inside a star. The gravitational field is repulsive and so a central singularity is avoided. The positive energy density and the pressures of the imperfect…

General Relativity and Quantum Cosmology · Physics 2020-05-05 Hristu Culetu

Neutral particles capable of travelling cosmic distances from a source to detectors on Earth are limited to photons and neutrinos. Examination of the Dark Matter annihilation/decay spectra for these particles reveals the presence of…

High Energy Physics - Phenomenology · Physics 2023-11-21 Wim Beenakker , Sascha Caron , Jochem Kip , Roberto Ruiz de Austri , Zhongyi Zhang

The uncertainties which still plague our understanding of the evolution of the light nuclides D, 3He and 4He in the Galaxy are described. Measurements of the local abundance of deuterium range over a factor of 3. The observed dispersion can…

Astrophysics of Galaxies · Physics 2015-05-14 Donatella Romano

We investigate deuterium atoms adsorbed on the surface of liquid helium in equilibrium with a vapor of atoms of the same species. These atoms are studied by a sensitive optical method based on spectroscopy at a wavelength of 122 nm,…

Condensed Matter · Physics 2009-10-31 A. P. Mosk , M. W. Reynolds , T. W. Hijmans

As proposed recently by Fornal and Grinstein, neutrons can undergo a dark matter decay mode which was not observed before. Such a decay could explain the existing discrepancy between two different methods of neutron lifetime measurements.…

Nuclear Experiment · Physics 2018-05-02 Marek Pfützner , Karsten Riisager

We identify stars in the $\delta$ Sct instability strip that do not pulsate in p modes at the 50-$\mu$mag limit, using Kepler data. Spectral classification and abundance analyses from high-resolution spectroscopy allow us to identify…

Solar and Stellar Astrophysics · Physics 2015-06-23 Simon J. Murphy , Timothy R. Bedding , Ewa Niemczura , Donald W. Kurtz , Barry Smalley

Understanding the origin of the elements has been a decades long pursuit, with many open questions still remaining. Old stars found in the Milky Way and its dwarf satellite galaxies can provide answers because they preserve clean elemental…

Solar and Stellar Astrophysics · Physics 2018-11-14 Anna Frebel

The cosmological abundance of nucleons determined from considerations of Big Bang nucleosynthesis allegedly provides compelling evidence for non-nucleonic dark matter. Recent developments in measurements of primordial light element…

Astrophysics · Physics 2007-05-23 Subir Sarkar

The primordial abundance of deuterium (D/H) yields a measure of the density of baryons in the universe and is an important complement to determinations from cosmic microwave background (CMB) experiments. Indeed, the current small sample of…

Astrophysics · Physics 2009-11-13 Sara L. Ellison , Jason X. Prochaska , Sebastian Lopez

A complete set of linearly independent observables in Compton scattering with arbitrarily polarised real photons off an arbitrarily polarised spin-1 target is introduced, for the case that the final-state polarisations are not measured.…

Nuclear Theory · Physics 2018-04-12 Harald W. Griesshammer